The BoomBox MP3 Module is a module that stores and plays the MP3 files when BoomBox is triggered. To load the MP3s, detach the module from the BoomBox board and connect it to your computer via a USB Mini cable. It will show up as an external drive. Then drop and drag the MP3s onto the module before reattaching to the BoomBox board.
The BoomBox MP3 Module comes with 16 MB of memory (approximately 15 minutes of audio) and can play back .wav and .mp3 files. Purchasing extra MP3 modules allows you to swap out sounds and playlists while devices are deployed in the field without needing a computer. You just remove the old MP3 module and replace it with the new one.